Problem n. 1: Burebista and the Bastarnae.
Using Strabo as our main source, we start with the following basis: (7,3,11):
"Boerebistas, a Getan, on setting himself in authority over the tribe, restored the people, who had been reduced to an evil plight by numerous wars, and raised them to such a height through training, sobriety, and obedience to his commands that within only a few years he had established a great empire and subordinated to the Getae most of the neighbouring peoples. And he began to be formidable even to the Romans, because he would cross the Ister with impunity and plunder Thrace as far as Macedonia and the Illyrian country"
I would distinguish four periods here: (1) Burebista becomes lord of all Getans (3) Burebista trains them (3) imperial expansion over neighbours (4) raids against Roman territories. Though of course there can be overlaps. For instance what follows next in Strabo ("and he not only laid waste the country of the Celti who were intermingled with the Thracians and the Illyrians, but actually caused the complete disappearance of the Boii who were under the rule of Critasirus, and also of the Taurisci") could belong to period (3) no less than to (4).
I think the key here is the phrase "within only a few years". Many commentators, basing themselves on a passage in Jordanes which suggests that Burebista's advisor Dicineus came to Getia and was accepted by Burebista during the time of Sulla (d. 78 BCE) expand the Getan ruler's reign considerably (the favoured starting point being 82 BCE). We have no way of determining this issue. It is entirely possible that the duo began to function when Burebista was still a minor lord of some Getan subgroup, and that phases (1) and (2), themselves overlapping, could have lasted much longer than Strabo's time frame for the imperial expansion.
It seems however safe to say that there is no clear evidence that phase (3) let alone (4) began much prior to 60 BCE if not even a little later. I suspect that "within only a few years" means just that, and that Strabo is talking about a decade or thereabouts.
We have a couple of notices about the Bastarnae shortly before the beginning of Burebista's empire building. Both s.a. 61 BCE. There is Cassius Dio's account of the help they vouchsafed to the citizens of Histria against the depredations of the Roman proconsul of Macedonia C. Antonius. These would be "Peucini" (still using the Danube delta island). And there is the list found in Pliny NH 7.98 of "participants" (as war trophies..) in Pompey's Roman triumph of 29 September in that year. Interestingly, only Bastarnae and "Scythians" are mentioned as representatives of erstwhile Mithridatian "barbarian" allies from the northern Black Sea area among paraded captives. Perhaps they were made prisoners during the campaign in Pontus in 66, and belonged to the draftees (volunteers or mercenaries) of 67.
The Bastarnae undoubtedly were among the "neighbours" subjected to Burebista's growing power. There is no extant historical documentation about this, but archaeological evidence demonstrates the fact quite convincingly. Of the groups mentioned earlier, the most affected were those of Poeneshti-Lukashovka in Moldavia and group 2 of Zarubinia on the Central Dnipro (groups 1 and 3 continued to develop as before). We have no precise dates, but there is no doubt that by the mid-first century BCE, Poeneshti-Lukashovka ceased to exist in its traditional territory, which thereafter became exclusively Getic in culture. This extinction was apparently not the result of military destruction, but of out-migration. Poeneshti-Lukashovka relocated in the north, on the territory of the contemporary Chernivtsi (Czernowitz/Cernauti) region of Ukraine, with some settlements in southeasternmost Galicia. There was also movement southward towards the
Danube (but it is unclear whether this occurred simultaneously or was part of a reflux subsequent to Burebista's downfall and the disintegration of his construct). In any case, the pattern of locale change from Moldavia to Western Ukraine reminds one of the population shifts of the Farzoi era, and suggests that Burebista may have had similar policies. It is arguable that the Poeneshti-Lukashovkan Bastarnae accepted Burebista's overlordship without much resistance (there was no sign of violence, destruction by fire or anything of the kind on the abandoned sites, and the new settlements were not fortified). The situation was different on the territory of group 2.
The Central Dnipro Bastarnian group had very strong economic relations with Olbia and with the Lower Dnipro Scythians. Sometime near the end of the first half of the 1rst century BCE, a large proportion of their previously "open" settlements were turned into fortresses with earthen walls and strong stockades (more than 30 such). At about the same time as Olbia was being destroyed by the Getae (according to Dio Chrysostomus' "Borysthenite oration" this happened ca. 50 BCE) there was a massive attack on these Bastarnian fortresses (and on the cities of Lower Dnipro Scythia). All of the stockades were burned down, and the presence of many Sarmatian arrows tips at their excavation level indicated that the attackers were the Iazigi. This indicates that the Iazigi also became Burebista allies. There is however no abandonment of any group 2 Bastarnian site, which continued to exist, but without fortifications. The
intimation being that this group was defeated and vassalized, but not expulsed. Some time later, perhaps twenty years or so, at about the same time as the revival of Scythian power and the second founding of Olbia, we find all of the group 2 fortresses being rebuilt (new stockades), and the reestablishment of traditional economic ties with the Scythians, with Scythian quarters in the north and group 2 Bastarnian cemeteries in the Scythian cities of the south. But it seems that in Burebista's time Getan power had stretched all the way to the Dnipro and further north. There seems no reason why groups 1 and 3 of northern Bastarnia would not also have been affected.
(to be continued)